Device for individualizing fibers, and spinning device comprising such a device

ABSTRACT

The invention relates to a device ( 1 ) for individualizing fibers of a supplied fiber sliver end and to a spinning device ( 2 ) comprising such a device ( 1 ). The device ( 1 ) comprises a first hollow body section, to which pressure can be applied and which comprises an inlet channel segment ( 3 ) for receiving and guiding a supplied fiber sliver end together with a fluid in the direction of an unraveling channel segment ( 6 ) arranged downstream thereof, and the unraveling channel segment ( 6 ), which communicates with the inlet channel segment ( 3 ) and is arranged downstream thereof, for unraveling the fiber sliver end supplied together with the fluid into individual fibers. The unraveling channel segment ( 6 ) forms an annular channel ( 10 ) which communicates with the inlet channel segment ( 3 ). The annular channel ( 10 ) has a channel inlet ( 11 ) with a first passage width and a channel outlet ( 12 ) at a distance therefrom with a second passage width, wherein in a section extending from the first passage width to a central passage width of a channel center arranged between the channel inlet ( 11 ) and the channel outlet ( 12 ), the passage width of the annular channel ( 10 ) tapers constantly or in sections such that the central passage width is smaller than the first passage width.

The present invention relates to a device for individualizing fibers of a fed sliver end; to a spinning device comprising a device of this type; and to a method for spinning a thread by means of the spinning device.

Individualizing fibers is an essential preliminary step for spinning a thread from separated fibers, as in open-end spinning methods in particular. In comparison with other spinning methods such as ring spinning, open-end spinning methods are characterized in that a sliver consisting of parallelised fibers is opened into individual fibers and these individual fibers are spun onto an open end of a spun thread. Such an open-end spinning method is represented by the rotor spinning method, for example. In the rotor spinning method, a sliver end consisting of parallelised fibers is fed to a rotating opening roller, which detaches the individual fibers from the sliver end, carries them along and feeds them to a fiber guide channel leading to a spinning rotor. The individual fibers fed to the spinning rotor via the fiber guide channel slide along a fiber slide wall formed by the rotor cup of the spinning rotor into a rotor groove of the rotating spinning rotor, in which rotor groove the individual fibers are accumulated and are doubled to the desired yarn count and via which rotor groove the fiber accumulation is fed to a thread end in order to spin a thread. Such an open-end rotor spinning method is known from the document DE 10 2008 050 071 A1, for example.

The open-end spinning methods also include the air spinning method. In contrast to the rotor spinning method, which is based on an aeromechanical principle, the air spinning method is based on an aerodynamic principle. In the air spinning method, a sliver which has been drafted in a defined way is fed to an air-spinning nozzle unit. The drafting causes a reduction in the fiber quantity per unit length. The air-spinning nozzle unit comprises a sliver inlet with downstream injector nozzles for producing a vortex flow in a vortex chamber, into which a cone of a thread-forming element extends. A thread guide channel extends through the cone, and the spun thread can be led out of the air-spinning nozzle unit through the thread guide channel. By means of the vortex flow produced in the vortex chamber, edge fibers of the fed sliver which consists of parallelised fibers are laid around the cone without completely detaching from the sliver. The core fibers are led into the thread guide channel. In the inlet region of the thread guide channel, the transport movement of the core fibers into the thread guide channel causes the edge fibers lying around the cone to be pulled along in such a way that these edge fibers wrap around the parallelised core fibers and form what are called wrap fibers, and thus a thread is spun from the parallelised core fibers and the wrap fibers. Such an air spinning method is known from the document EP 1 584 715 A1, for example. However, complete separation of the fed sliver is not achieved in the air spinning method.

The process of individualizing fibers, whether completely as in rotor spinning methods or partially as in the air spinning method, is highly significant to the achievable quality of a spinning thread. The fiber separation achievable by means of an opening roller in the rotor spinning method requires an opening roller device which takes up corresponding installation space and which has a large number of components of complex design. The same applies to the air-spinning nozzle unit in the air spinning method.

An alternative, more simplified device for individualizing fibers, in particular with fewer complex components, a spinning device, and a method for spinning a thread using the device and the spinning device should be proposed by means of the present invention.

The device for individualizing fibers which is proposed by means of the present invention comprises a pressurisable hollow body portion, which has an inlet channel segment for the fluid-accompanied receiving of a fed sliver end and guiding of the fed sliver end toward a downstream opening channel segment, and the opening channel segment, which is arranged downstream of the inlet channel segment in the guiding direction of the sliver end and in communication with the inlet channel segment and which is designed to open the fluid-accompanied fed sliver end into individual fibers. According to the invention, the opening channel segment forms an annular channel which communicates with the inlet channel segment and which has a channel inlet having a first passage width and a channel outlet spaced apart from the channel inlet in the guiding direction of the sliver and having a second passage width, the passage width of the annular channel tapering, throughout or in parts, in a portion from the first passage width to a middle passage width of a channel middle located between the channel inlet and the channel outlet, such that the middle passage width is less than the first passage width. In other words, the annular channel tapers from the channel inlet toward the channel middle, in particular continuously or in steps. The geometric design of the opening channel segment according to the invention allows an increase, in particular a growing increase, in the flow velocity of the sliver-end-accompanying fluid toward the channel middle, whereby the fed sliver, which in particular consists of parallelised fibers, can be opened into individual fibers. Furthermore, drawing of the detaching and opened individual fibers can advantageously be achieved if the annular channel has, between the channel inlet and the channel middle, an inside surface which is suitable for producing a laminar fluid flow. The inside surface delimiting this annular channel portion is particularly preferably edge-free. In the sense of the present invention, “edge-free” should be understood to mean such a transition between two surface portions that turbulent flows can be largely prevented. For example, this can be achieved if the passage width of the annular channel is reduced as continuously as possible between the channel inlet and the channel middle, in particular from the channel inlet to the channel middle.

According to a preferred embodiment of the present invention, the inlet channel segment has a conically tapered receiving portion for the sliver. Thus, the sliver can be reliably fed and can already be guided with an increasing flow velocity acting on the sliver toward the annular channel. This allows the sliver to be slightly pre-drafted sufficiently to prevent potential fiber balls during the feeding of the sliver. The length of the inlet channel segment in the guiding direction can be suitably chosen in accordance with the fiber material to be opened.

It is also preferred that the inlet channel segment comprises, adjacent to the conically tapered receiving portion, an identical-diameter cylindrical passage portion for transferring the sliver end to the channel inlet. In dependence on the length of the identical-diameter cylindrical passage portion in the guiding direction, the increase in the flow velocity can be appropriately matched to the fiber material to be opened. In an additionally preferred embodiment, at least the component of the device which comprises the cylindrical passage portion can form an exchangeable component, or alternatively the inlet channel segment can form an exchangeable component, so that variability of the device for different fiber materials to be opened can be ensured.

An inside diameter of the channel inlet is preferably less than a corresponding inside diameter of the channel middle. The inside region of the annular channel assumes a cross-sectional cone shape with the cone tip in the region of the channel inlet and the cone base in the region of the channel middle. Such a cone shape promotes the detachment of the individual fibers from the sliver as the sliver end enters the channel inlet.

A core element is preferably supported in the passage of the opening channel segment in order to form the annular channel. The core element therefore has such an outer shape that, between an inner surface or inside wall of the opening channel segment and the outer surface or outside wall of the core element, an annular gap forming the annular channel and having a passage width as described above is formed, through which annular gap the sliver or the opened individual fibers can be led, accompanied by fluid.

It is also preferred that the core element is supported by means of at least one supporting element connecting the opening channel segment to the core element. The supporting element therefore extends from the inside wall of the passage of the opening channel segment to the opposite outside wall of the core element. The supporting element can be arranged within the annular channel at the desired point. The supporting element preferably has an aerodynamic shape in order to reduce an interfering influence on the fluid flow. In the sense of the present invention, “aerodynamic shape” is understood to mean a shape which is suitable for causing the slightest possible vortices to no vortices in order to prevent turbulent flow in the fluid flow. For example, the supporting element can be formed by means of a bar which is as aerodynamic as possible. For example, the supporting element can cross-sectionally constitute a teardrop shape extending in the guiding direction of the sliver or of the individual fibers, it being additionally preferred that the teardrop shape is designed and arranged such that the teardrop tip points against the guiding direction of the sliver or of the individual fibers and the spherical teardrop side faces in the guiding direction. Preferably, the teardrop-like design of the supporting element can alternatively or additionally run transversely to the guiding direction, i.e. between the core element and the opening channel segment. In this case, the teardrop tip is connected to the core element and the teardrop base is connected to the inside wall of the passage of the opening channel segment. The teardrop-like design of the supporting element reduces the risk that fibers wind or wrap around the supporting element, which can lead to clogging of the opening channel segment. It is also preferred that the length of extent of the supporting element in the guiding direction is greater than the greatest fiber length of the individual fibers of the fed sliver which are to be opened. This allows a further reduction of the risk that fibers become wrapped.

The supporting element can preferably have a front end which faces toward the inlet channel segment and which is arranged in a passage region of the inlet channel segment, the supporting element extending into the opening channel segment in the guiding direction. In other words, the supporting element extends in the radial direction of the device both from the inside wall of the passage of the inlet channel segment and from the inside wall of the passage of the opening channel segment to the opposite outside wall of the core element. Alternatively the supporting element, with its front end, can extend in the guiding direction from a plane containing the channel inlet, the supporting element being arranged exclusively in the passage region of the opening channel segment. The supporting element can also preferably be designed as a ramp for the sliver to be fed to the core element, the ramp leading from an inside wall of the passage of the inlet channel segment and/or of the opening channel segment to the outside surface of the core element. The ramp thus connects, along the guiding direction, the surface side of the inside wall of the inlet channel segment and/or of the opening channel segment to the surface side of the outside wall of the core element, whereby a defined guide surface portion for the sliver to be opened can be provided along the guiding direction. Furthermore, the core element can thereby be reliably supported at the same time.

In the case of the preferred embodiment of a ramp formed from the inside wall of the inlet channel segment to the outside wall of the core element, the guide surface portion formed by the ramp can preferably have a shape suitable for guiding the sliver. For example, the guide surface portion can be flat, curved and/or stepped along the guiding direction and/or transversely thereto. The guide surface portion can also preferably have, along the guiding direction, such an inclination angle that allows a smooth transition of the sliver guidance between the ramp and the outside wall of the core element. The inclination angle of the guide surface portion is preferably greater than, identical to, or less than the inclination angle of the outside wall portion of the core element that is formed from the front end of the core element facing the inlet channel segment toward the middle passage width. The smaller the difference between the two inclination angles is, the more smoothly the sliver guidance can transition from the ramp to the outside wall of the core element. Of course, it is also conceivable that the guide surface portion has different inclination angles, in which case the inclination angles of at least two guide surface intermediate portions transitioning into each other can differ such that the one guide surface intermediate portion is greater than or less than the other. The inclination angles of the guide surface intermediate portions are preferably such that the magnitude of the difference of these inclination angles from the inclination angle of the outside wall portion decreases in the guiding direction, whereby a smooth transition can be made possible.

It is particularly preferred that more than one supporting element is provided so that the core element is more reliably supported. For example, two or three or more supporting elements can be provided, which can be arranged circumferentially around the core element, in particular in a circular or spiral arrangement direction, more preferably in a uniform distribution.

Alternatively or in addition to the supporting element, the core element can preferably be held in the opening channel segment by means of magnetic supporting forces. For example, this can be implemented by means of a controllable electromagnet, by means of which the core element reacting to the producible magnetic forces can be supported within the opening channel segment in a defined way or as required and, in particular, stably. For this purpose, the core element has a material which reacts to magnetic forces, this material being arranged in or on the core element and making it possible to stably support the core element within the opening channel segment under the influence of magnetic forces. For example, the core element can be made of such a material or can have a corresponding material in suitable locations.

It is also preferred that the core element, in particular as a result of being purely magnetically supported within the opening channel segment, is supported such that the core element can be rotated in its circumferential direction. This can be achieved, for example, by suitable design and control of the electromagnet.

It is alternatively preferred that the core element held by means of the at least one supporting element can comprise a partial element which can be rotated by mechanical driving means or by magnetically acting rotational forces, said partial element being arranged on a side of the core element remote from the channel inlet and being rotatably held by the additional partial element of the core element, which is held by the at least one supporting element. The mechanical driving means can be arranged in the additional partial element. In the case of the magnetic rotation drive, the partial element is suitably designed for interaction with the acting magnetic rotational forces.

According to a preferred embodiment of the present invention, the device can be formed as a single part or as multiple parts, it also being preferred that at least one part of the device is formed by means of a machining method and/or an additive manufacturing method. In particular, the additive manufacturing method is suitable for avoiding joints and connection points. Possible additive manufacturing methods are, for example, 3D printing, selective laser melting (SLM), electron beam melting (EBM), binder jetting (BJ), fused deposition modelling (FDM) or laser sintering, each particularly with materials made of metal. Additionally, subsequently or alternatively, a sintering process and/or a treatment or processing of the surface can also be carried out in order to achieve appropriate quality.

A method in which the device or the at least one device part is formed from ceramic and/or by means of stereolithography (SLA) is particularly preferred. If, however, the device or the at least one device part should be formed from metal, production by means of laser sintering, in particular selective laser sintering (SLS), is preferred. Alternatively, the device or the at least one device part can also be formed in a different way, more particularly from metal, and subsequently sintered. Furthermore, it is possible to form a device consisting of a plurality of device parts by means of the jointless and/or integral interconnecting of at least two device parts, in particular the inlet channel segment and the opening channel segment, by sintering or in another way.

According to another aspect of the present invention, a spinning device is proposed, which has a device for individualizing fibers according to one of the preferred embodiments described above, wherein the passage width of the annular channel expands, throughout or in parts, in a portion from the middle passage width or from the channel middle to the second passage width or to the channel outlet, such that the middle passage width is less than the second passage width. In other words, the annular channel expands again, in particular continuously or in steps, from the channel middle toward the channel outlet, since the middle passage width is less than the second passage width. It is also preferred that the inside wall delimiting this annular channel portion is designed edge-free in a way such as is described as preferred above. This allows defined and controlled guidance of the detached individual fibers, while avoiding interfering vortices in the accompanying fluid flow.

The spinning device advantageously also comprises a second pressurisable hollow body portion, which has a spinning segment for spinning a thread from the fed individual fibers, the spinning segment being arranged downstream of the opening channel segment in the guiding direction of the sliver end or of the individual fibers and in communication with the opening channel segment in order to receive and double the detached and, in particular, drawn individual fibers, and the spinning segment being assigned a swirling means for producing a vortex flow for producing a real-twist spinning thread, which vortex flow swirls the individual fibers together. As an alternative to the spinning methods which are already well known, such as ring spinning and rotor spinning, a real-twist yarn or a real-twist spinning thread can likewise be produced by means of the spinning device, in which case the device responsible for producing the yarn or thread has a simpler design with less complex components.

According to a preferred embodiment of the present invention, the channel middle is arranged closer to the channel inlet than to the channel outlet. In other words, the annular channel is designed such that a path of the sliver or of the individual fibers from the channel inlet to the channel middle is shorter than a path of the sliver or of the individual fibers from the channel middle to the channel outlet. The opened individual fibers can thus be led out of the annular channel in a more controlled and more reliable way for subsequent processing operations and/or treatment operations such as the twisting under the influence of a swirling fluid flow in order to produce a real-twist spinning thread.

According to a preferred embodiment of the present invention, the core element forms a double cone which extends between the channel inlet and the channel outlet and which has congruent bases near or in the passage plane of the channel middle. The core element thus can be formed exactly, i.e. with small tolerances, and in such a way that installation space can be reduced, and economically.

The design of the annular channel preferably follows the following formula:

$D_{outside} = \sqrt{A - D_{inside}{}^{2} - A_{bar}}$

with

-   D_(outside): outside diameter of the annular channel -   A: cross-sectional area of the annular channel (at any point of the     annular channel along the guiding direction) -   D_(inside): inside diameter of the annular channel -   A_(bar): cross-sectional area of the supporting element (at any     point of the supporting element along the guiding direction), with     the condition that A_(bar) = 0 at the points at which there is no     supporting element.

Observing this formula allows an aerodynamically optimised annular channel.

The swirling means is preferably formed by the magnetically supported rotatable core element or by the partial element. By means of defined rotation of the core element or of the partial element, required vortices for producing the spinning thread from the individual fibers can be produced in the fluid flow in a specific way.

Alternatively, the core element can be supported within the first hollow body portion of the device purely by means of the fed fluid flow. In other words, when fluid is not fed to the device, the core element is deposited on a lower inside wall of the opening channel segment as a result of gravity. After a fluid flow is fed, the core element is raised into and held in a stable position nearly centrally or centrally within the passage of the opening channel segment. For this purpose, the core element has a correspondingly suitable shape such as the double cone shape described as preferred above. Essential to the lifting off is a cone tip of the core element formed against the guiding direction or the fluid flow direction, so that it can be ensured that the core element is lifted into the central position by fluid flow when fluid flow is supplied.

It is also preferred that the core element supported by fluid flow can be rotatably supported, whereby the core element also can form the swirling means. The rotation can be produced in particular by the action of magnetic force, for example according to one of the preferred embodiments described above.

According to a preferred embodiment, in particular an alternatively preferred embodiment, the spinning segment has at least two injector nozzles as part of the swirling means or as the swirling means, the injector nozzles being arranged circumferentially at the inside wall of the spinning segment, and the injector nozzles being arranged and designed to introduce a vortex flow which runs around a central axis of the spinning segment and along said central axis, whereby a vortex flow can be produced in the spinning segment in order to produce the real-twist spinning thread from the individual fibers fed into the spinning segment. For example, a defined injector nozzle channel portion ending in the injector nozzle opening can be formed both at an angle to the circumferential direction of the inside wall of the spinning segment and at an angle to the guiding direction of the individual fibers or to the passage direction of the spinning segment in order to introduce a vortex flow, in particular a controllable vortex flow, directed along the inside wall of the second spinning segment in the guiding direction or passage direction.

According to a preferred embodiment, the injector nozzles can be provided, individually or in combination with the rotatable design of the core element, for causing a defined vortex flow within the spinning segment, on the basis of which vortex flow the real-twist spinning thread can be produced.

The spinning device or parts of the spinning device can preferably be produced, in a previously described way, by means of a machining method and/or an additive manufacturing method. In this case or according to another preferred embodiment, the spinning device or the first hollow body portion of the device and the second hollow body portion can be of a single-part or multi-part design in accordance with requirements.

According to another aspect of the present invention, a method for spinning from separated fibers using a spinning device according to one of the preferred embodiments described above is proposed. The method comprises a step of feeding a sliver end, accompanied by fluid, in particular by air, into the inlet channel segment and a step of operating the swirling means in order to spin a thread from the individual fibers fed via the opening channel segment into the spinning segment. The feeding with accompanying air can be accomplished preferably by compressed-air feeding by means of compressed-air nozzles assigned to the inlet channel segment. The compressed-air nozzles can be upstream of the inlet channel segment along the sliver feed path. Alternatively or additionally, the feeding with accompanying air can be accomplished by the production of a suction air flow in the inlet channel segment by means of injector nozzles, which are arranged in the inlet channel segment or downstream of the inlet channel segment along the sliver feeding direction. For example, the injector nozzles can also form the swirling means.

According to a preferred embodiment, the method comprises a step of controlling the sliver feed, the fluid flow accompanying the sliver and/or the operation of the swirling means in order to produce a spinning thread meeting the requirements. For example, the feeding speeds of the sliver and/or of the fluid flow accompanying the sliver can be adjusted. Alternatively or additionally, the operation of the swirling means can be adjustable in a defined way so that the spinning process can be suitably adapted. The adjustment and/or control of the systems in question can preferably be accomplished on the basis of measurement values, which can be transmitted from a sensor system for capturing suitable measurement data of the systems in question. The sensor system can be provided at corresponding suitable points of the spinning device. This also promotes an automated spinning process that can be controlled by closed-loop and/or open-loop control.

Further features and advantages of the invention will become clear from the following description of a preferred embodiment example of the invention, on the basis of the figures and drawings illustrating details essential to the invention, and from the claims. The individual features can be implemented individually or in any desired combination in a preferred embodiment of the invention.

A preferred embodiment example of the invention is explained in more detail below on the basis of the accompanying drawings.

In the drawings:

FIG. 1 shows a schematic side view of a spinning device according to an embodiment example,

FIG. 2 shows a schematic perspective longitudinal section view, along the section plane A-A, of the spinning device shown in FIG. 1 ,

FIG. 3 shows a schematic perspective cross-section view, along the section plane B-B, of the spinning device shown in FIG. 1 ,

FIG. 4 shows a schematic front view of the spinning device shown in FIG. 1 ,

FIG. 5 shows a schematic rear view of the spinning device shown in FIG. 1 , and

FIG. 6 shows a schematic perspective longitudinal section view, along the section plane A-A, of the spinning device shown in FIG. 1 , according to an alternative embodiment example.

FIG. 1 shows a schematic side view of a spinning device 2 according to an embodiment example. The spinning device 2 is functionally divided into a plurality of portions along its longitudinal extension direction LE. An end portion shown on the left side in FIG. 1 defines an inlet channel segment 3 for the fluid-accompanied receiving and guiding of a fed sliver end. A middle portion adjoining the inlet channel segment 3 is designed as an opening channel segment 6. The end portion opposite from the inlet channel segment 3, with the opening channel segment 6 located therebetween, defines a spinning segment 13 having injector nozzles 14. These three functional portions are essential to the spinning device 2 according to this embodiment example. According to another embodiment example, which is not shown, additional portions which are functionally appropriately designed can be provided. For example, a functionally independent outlet segment for discharging or take-up portion for taking up the spun thread could be assigned to the spinning segment 13. In the embodiment example shown, at least the outlet portion is assigned to the spinning segment 13 and is a part thereof, as described in greater detail below.

FIG. 2 shows a schematic perspective longitudinal section view, along the section plane A-A, of the spinning device 2 shown in FIG. 1 . The spinning device 2 is formed as a single piece from a pressurisable hollow body symmetrical with respect to its longitudinal central axis LM, which extends along the direction of longitudinal extent LE. The end-arranged inlet channel segment 3 has a receiving portion 4, which is conically tapered toward the opening channel segment 6 along the direction of longitudinal extent LE and which transitions into a cylindrical passage portion 5 so that the sliver or sliver end received by means of the receiving portion 4 is reliably guided, with accompanying fluid, toward the opening channel segment 6. A gaseous medium such as ambient air is preferably used as the fluid. Thus, the spinning device 2 does not have to be sealed off from the ambient air. In order to support the guiding of the sliver with accompanying fluid, the inlet channel segment 3 can preferably comprise, in the region of the cylindrical passage portion 5, nozzles which are directed toward the downstream opening channel segment 6 and by means of which the fluid can be introduced into the cylindrical passage portion 5. A suction flow can thus be produced in the region of the receiving portion 4, whereby the sliver can be reliably led into the inlet channel segment 3 or into the spinning device 2.

Alternatively, according to an embodiment example not shown, it would be possible to arrange the nozzles outside of the spinning device 2 upstream of the receiving portion 4 in such a way that the nozzles are directed toward the receiving portion 4.

As another alternative, such nozzles can be absent as in the embodiment example shown, in which case the ambient air present anyway accompanies the fed sliver in the spinning device 2 and defined fluid flows within the spinning device 2 can be produced at least by means of the injector nozzles 14 arranged in the spinning segment 13, supported by a passage cross-section which changes along the direction of longitudinal extent LE. In this embodiment example, the guiding direction of the sliver is oriented substantially along the direction of longitudinal extent LE of the spinning device 2.

The inlet channel segment 3 is adjoined, in the guiding direction of the sliver that can be fed, by the opening channel segment 6 for opening the fluid-accompanying fed sliver end into separated fibers. For this purpose, according to this preferred embodiment example the opening channel segment 6 has a core element 8 in the form of a double cone, the double cone being symmetrical with respect to the longitudinal central axis LM and asymmetrical with respect to a common cross-sectional plane which is perpendicular to the longitudinal central axis LM and in which the bases of the two cones forming the double cone are arranged. The core element 8 has rounded first and second cone tips 8 a, 8 b at respective ends of the core element 8. In this embodiment example, the core element 8 is arranged centrally within the passage portion of the opening channel segment 6 in order to form an annular channel 10 which is uniform along the direction of longitudinal extent LE at each point of the core element 8, and the core element 8 is held by means of three supporting elements 9 evenly distributed circumferentially around the core element 8 (FIGS. 3 and 4 ). The supporting elements 9 are arranged close to the first cone tip 8 a directed toward the inlet channel segment 3 and have an aerodynamic teardrop shape running transversely to the direction of longitudinal extent LE, such that the teardrop tip is arranged on the core element 8 and the teardrop base is arranged on the inside wall 7. The teardrop width running in the circumferential direction of the core element 8 is approximately constant along the direction of longitudinal extent LE. Taking aerodynamic aspects into account, according to this embodiment example each supporting element 9 is tapered toward the inlet channel segment 3, likewise in a teardrop shape, as shown in FIG. 3 . Thus, turbulent fluid flows which would otherwise be possible can be prevented. As FIG. 3 also indicates, the teardrop depth running along the direction of longitudinal extent LE perpendicularly to the teardrop width is selected such that the core element 8 can be held reliably and, to the extent possible, without evasive movements and/or vibrations at the second cone tip 8 b directed away from the inlet channel segment 3. At the same time, the selected teardrop depth is greater than the greatest fiber length of the fiber material to be opened, so that the risk that fibers wrap around the supporting elements 9 can be reduced.

The passage portion of the opening channel segment 6 and the core element 8 are matched to each other in such a way that a uniform annular channel 10 is formed which has a channel inlet 11 at the first cone tip 8 a, the channel inlet 11 having a first passage width, and a channel outlet 12 at the second cone tip 8 b, the channel outlet 12 being spaced apart from the channel inlet 11 and having a second passage width, and the passage width of the annular channel 10 tapers, throughout or in parts, in a portion from the first passage width to a middle passage width of a channel middle located between the channel inlet 11 and the channel outlet 12, such that the middle passage width is less than the first passage width. The tapering design causes the flow velocity to increase toward the channel middle.

In contrast, in this embodiment example the passage width increases from the channel middle to the channel outlet 12 (in particular throughout or in parts). This causes the flow velocity to decrease in a defined way. The degree of tapering and the degree of expansion of the passage width over the length of extent of the annular channel 10 can be selected appropriately for the sliver to be separated. The design of the annular channel 10 according to this embodiment example follows the formula below:

$D_{outside} = \sqrt{A - D_{inside}{}^{2} - A_{bar}}$

with

-   D_(outside): outside diameter of the annular channel -   A: cross-sectional area of the annular channel (at any point of the     annular channel along the guiding direction) -   D_(inside): inside diameter of the annular channel -   A_(bar): cross-sectional area of the supporting element (at any     point of the supporting element along the guiding direction), with     the condition that A_(bar) = 0 at the points at which there is no     supporting element.

The outside diameter of the annular channel 10 corresponds, in this embodiment example, to the inside diameter of the passage of the opening channel segment 6. The inside diameter of the annular channel 10 corresponds, in this embodiment example, to the outside diameter of the core element 8. The cross-sectional area of the annular channel 10 logically results from the area portion enclosed by the outside diameter and the inside diameter of the annular channel 10. At the points at which a supporting element is present, the cross-sectional area of the supporting element consists of the total of the individual cross-sectional areas of the supporting elements 9.

Observing this formula allows an aerodynamically optimised annular channel.

The inlet channel segment 3 designed, by way of example, according to this embodiment example, together with the opening channel segment 6, therefore forms a device 1 for individualizing fibers of a fed sliver end. By means of the combination of these portions, suitable devicees 1 for the defined fiber separation of a fed sliver end which are each adapted to a different sliver material can be provided.

Although the device 1 according to this embodiment example is of a single-piece design, the device 1 can also be of a multi-part design according to an embodiment example not shown, wherein, by way of example, the inlet channel segment 3 and the opening channel segment 6 each form an independent part, the independent parts being accordingly interconnected by means of common fastening/connecting measures. In the case of the multi-part design, it is also preferred that the individual parts are nondestructively exchangeable, whereby the variability can be increased.

Along the direction of longitudinal extent, the opening channel segment 6 is followed, on the side opposite from the inlet channel segment 3, by the spinning segment 13. The spinning segment 13 has an additional passage portion 15, which is communicatively connected to the channel outlet 12 and continues from the channel outlet 12 toward the end of the spinning device 2 opposite from the inlet channel segment 3. The spinning segment 13 has three injector nozzles 14 for feeding a vortex flow, in particular a compressed-air vortex flow, the injector nozzles 14 being arranged evenly around the additional passage portion 15 and being directed toward the end of the spinning device 2 opposite from the inlet channel segment 3. Thus, a suction flow is brought about in the opening channel segment 6, the suction flow extending into the inlet channel segment 3. The suction flow causes an increase in the flow velocity, whereby the fibers to be separated can be drawn. Furthermore, the circumferential arrangement and orientation of the injector nozzles 14 allows a vortex flow within the additional passage portion 15, which vortex flow extends into the passage portion between the channel middle and the channel outlet 12 of the annular channel 10. Thus, the fibers separated in the opening channel segment 6 experience a swirling impulse, by means of which the fibers can wrap around the second cone tip 8 b and can join together at the end of the opening channel segment 6 to form a real-twist spinning thread.

A fluid can be fed by means of the injector nozzles 14 with closed-loop and open-loop control in a known way. Together with the fed fluid, agents such as additives for adhering to the thread to be spun can also be fed by means of the injector nozzles 14, in order to influence the thread property appropriately. Such an agent feed can alternatively or additionally be arranged by providing corresponding feeds at a different point of the spinning device 2 or upstream of the inlet channel segment 3.

The spinning segment 13 comprises, downstream of the injector nozzles 14 in the spinning direction, an outlet portion 16, by means of which the spun thread can be led out of the spinning device 2 and can be fed to a thread handling element which is downstream of the spinning device 2 along the thread path. For example, a take-up device for taking up the spun thread from the spinning device 2, another device such as a sensor device for detecting a thread property such as hairiness or thick and thin places, or a thread accumulator for the intermediate storage of the spun thread can be arranged directly downstream of the spinning device 2. The outlet portion 16 has, opposite from the portion having the injector nozzles 14, an expanded passage portion, whereby the flow velocity and the vortex flows can be relaxed for the suitable discharge of the spun thread.

As is shown particularly by FIGS. 4 and 5 , which show a schematic front view and a schematic rear view of the spinning device 2 according to the embodiment example, a longitudinal central axis of the core element 8 is congruent with the longitudinal central axis LM of the hollow body or opening channel segment 6 surrounding the core element 8, and the supporting elements 9 are arranged close to the first cone tip 8 a or to the channel inlet 11 of the annular channel 10. Thus, the sliver end can be spread open when it enters the annular channel 10, and this has an advantageous effect on the opening of the sliver into individual fibers. Furthermore, after the sliver has been fed, the increase in the flow velocity along the direction of longitudinal extent LE of the device 1 up to the channel middle as a result of the design according to this embodiment example can cause the individual fibers to be reliably detached from the sliver and, at the same time, drawn. In this embodiment example, the injector nozzles 14 bring about the required vortex flow during operation, so that the detaching or detached individual fibers can be led around the conical portion of the core element 8 which follows the channel middle, within the annular channel 10, in such a way that these individual fibers are swirled or spun in the region of the second cone tip 8 b or just downstream thereof to form a real-twist spinning thread, which finally can be led out of the spinning device 2 by means of the outlet portion 16.

According to an embodiment example which is not shown, the swirling means is formed by the core element 8 itself or by the conical portion of the core element 8 following the channel middle. The former can be accomplished in particular by contactless support of the core element 8 within the passage of the opening channel segment 6, which contactless support can be implemented, for example, by means of a magnetic supporting device which, furthermore, preferably interacts with the core element 8 in such a way that defined rotational motions of the core element 8 can be brought about. Alternatively, the contactless support can be accomplished by means of the fed fluid flow, by means of which the core element 8 is lifted off, after the fluid flow is fed, from an idle position, in which the core element 8 is deposited on a lower inside wall of the passage of the opening channel segment 6 as a result of gravity, into an operating position, in which the core element 8 is held or supported nearly centrally or centrally within the passage of the opening channel segment 6 as a result of fluid flow. Provided that vortex flows are also introduced into the fed fluid flow, the core element 8 can be caused to rotate, in order to form the swirling means.

According to another embodiment example, which is not shown, the conical portion of the core element 8 following the channel middle forms the swirling means. This conical portion is rotatably supported by the preceding conical portion of the core element 8. The preceding conical portion is, as described above by way of example, held in the passage of the opening channel segment 6 by means of the supporting elements 9. The rotation of the following conical portion is brought about appropriately, with open-loop and/or closed-loop control, by means of a magnetically acting rotation device, by means of an introduced rotational flow, or by means of a rotation drive comprised by the preceding conical portion.

FIG. 6 shows a schematic perspective longitudinal section view, along the section plane A-A, of the spinning device 2 shown in FIG. 1 , according to an alternative embodiment example. This alternative embodiment example is distinguished from the embodiment example shown in FIG. 2 merely by an alternatively designed supporting element 9' and by an additional supporting element 9 in the region of the second cone tip 8 b, the additional supporting element 9 being arranged upstream of the second cone tip 8 b in the guiding direction of the sliver. The rest of the design is identical to the design of the embodiment example according to FIG. 2 ; identical reference signs correspond to components of the spinning device 2 which are described above accordingly, and reference is hereby made, for the alternative embodiment example, to the description of the embodiment example according to FIG. 2 .

The alternatively designed supporting element 9' is arranged in the region of the front end 8 a' of the core element 8, which front end 8 a' faces the inlet channel segment 3. The alternative supporting element 9' has a front end 9 a' which faces toward the inlet channel segment 3 and which is arranged in a passage region of the inlet channel segment 3, and the alternative supporting element 9' extends into the opening channel segment 6 in the guiding direction. The alternative supporting element 9' extends in the radial direction of the device 1 both from the inside wall of the passage of the inlet channel segment 3 and from the inside wall 7 of the passage of the opening channel segment 6 to the opposite outside wall of the core element 8 and forms a ramp 17 for the sliver to be fed to the core element 8. The ramp 17 thus connects, along the guiding direction, the surface side of the inside wall of the inlet channel segment 3 to the surface side of the outside wall of the core element 8, whereby a defined guide surface portion 18 for the sliver to be opened is provided along the guiding direction. The guide surface portion 18 is flat along the guiding direction and concave transversely thereto and has, in the guiding direction, an inclination angle that is 5° greater than the inclination angle of the surface portion of the outside wall of the core element 8 that adjoins the guide surface portion 18.

According to another embodiment example, which is not shown, the spinning device 2 preferably has a sensor system for monitoring e.g. the sliver feed, the fiber separation process, the spinning process and/or the take-up of the thread from the spinning device 2. The sensor system is arranged at suitable points of the device 1 and/or of the spinning segment 13, in or on the corresponding first or second hollow body portion. Alternatively or in addition, the portion of the spinning device 2 that comprises the annular channel portion to be monitored can be transparent. Thus, the sensor system can be arranged outside of the spinning device 2, allowing the sensor system to be economical and simplified.

The embodiment examples described above and shown in the figures are only selected by way of example. Different embodiment examples can be combined with one another completely or with regard to individual features. An embodiment example can also be supplemented with features of a further embodiment example.

If an embodiment example has an “and/or” link between a first feature and a second feature, this should be understood to mean that the embodiment example comprises, according to one embodiment, both the first feature and the second feature and, according to a further embodiment, either only the first feature or only the second feature.

LIST OF REFERENCE SIGNS

-   1 Device for individualizing fibers -   2 Spinning device -   3 Inlet channel segment -   4 Receiving portion -   5 Cylindrical passage portion -   6 Opening channel segment -   7 Inside wall -   8 Core element -   8 a First cone tip -   8 a' Front end of the core element -   8 b Second cone tip -   9 Supporting element -   9' Alternative supporting element -   10 Annular channel -   11 Channel inlet -   12 Channel outlet -   13 Spinning segment -   14 Injector nozzle -   15 Additional passage portion -   16 Outlet portion -   17 Ramp -   18 Guide surface portion -   LE Direction of longitudinal extent -   LM Longitudinal central axis 

1. A device (1) for individualizing fibers of a fed sliver end, the device (1) comprising: a first pressurisable hollow body portion, comprising: an inlet channel segment (3) configured to enable fluid-accompanied receiving of a fed sliver end and guiding of the fed sliver end toward a downstream opening channel segment (6); and the opening channel segment (6), configured to: open the fluid-accompanied fed sliver end into individual fibers; communicate with, and is arranged downstream of, the inlet channel segment (3); and form an annular channel (10) to communicate with the inlet channel segment (3), wherein the annular channel (10) comprises: a channel inlet (11) having a first passage width; and a channel outlet (12) spaced apart from the channel inlet (11) and having a second passage width, and wherein a passage of the annular channel (10) tapers, throughout or in parts, in a portion from the first passage width to a middle passage width of a channel middle located between the channel inlet (11) and the channel outlet (12), such that the middle passage width is less than the first passage width.
 2. The device (1) according to claim 1, wherein the inlet channel segment (3) comprises a conically tapered receiving portion (4) for the fed sliver end.
 3. The device (1) according to claim 2, wherein the inlet channel segment (3) comprises, adjacent to the conically tapered receiving portion (4), a cylindrical passage portion (5) to transfer the fed sliver end to the channel inlet (11).
 4. The device (1) according to claim 2, wherein the annular channel (10) is configured such that an inside diameter of the channel inlet (11) is less than a corresponding inside diameter of the channel middle.
 5. The device (1) according to claim 1, further comprising a core element (8), wherein the core element (8) is configured such that it is supported in the passage of the opening channel segment (6) in order to form the annular channel (10).
 6. The device (1) according to claim 5, wherein the core element (8) is supported in the opening channel segment (6) by one or more of the following: at least one supporting element (9) connecting the opening channel segment (6) to the core element (8); and magnetic supporting forces, wherein the core element (8) comprises, for a defined support of the core element (8) within the opening channel segment (6), a material configured to react to the magnetic supporting forces.
 7. The device (1) according to claim 6, wherein the core element (8) is supported such that it can be rotated in a circumferential direction.
 8. A spinning device (2) for spinning a thread, comprising: a device (1) configured to individual fibers according to claim 1, wherein the passage of the annular channel has a width that expands, edge-free, throughout or in parts, in a portion from the middle passage width to the second passage width, such that the middle passage width is less than the second passage width, and a second pressurisable hollow body portion (20), comprising a spinning segment (13) to spin a thread from the individual fibers, wherein the spinning segment (13): is arranged downstream of the opening channel segment (6) in a guiding direction of the fed sliver end, or downstream of the individual fibers, is in communication with the opening channel segment (6) in order to receive the individual fibers, and is assigned a swirling means for producing a vortex flow for spinning a thread, wherein the vortex flow is configured to swirl the individual fibers together.
 9. The spinning device (2) according to claim 8, wherein the channel middle is arranged closer to the channel inlet (11) than to the channel outlet (12).
 10. The spinning device (2) according to claim 8, further comprising a core element (8) configured to form a double cone which extends between the channel inlet (11) and the channel outlet (12) and which has congruent bases near or in a passage plane of the channel middle.
 11. The spinning device (2) according to claim 10, wherein the swirling means is formed by the core element (8).
 12. The spinning device (2) according to claim 11, wherein: the spinning segment (13) comprises at least two injector nozzles (14) as part of the swirling means or as the swirling means, and the injector nozzles (14) are arranged circumferentially at an inside wall of the spinning segment (13), and are provided for producing a swirling flow in the spinning segment (13).
 13. The spinning device (2) according to claim 12, wherein the spinning device (2), the device (1), or the spinning segment (13) is formed as a single part or as multiple parts, by means of one or more of the following: a machining method; and an additive manufacturing method.
 14. A method for spinning a thread from separated fibers, comprising: providing a spinning device (2) according to claim 8; feeding a the fed sliver end, accompanied by fluid, into the inlet channel segment (3); and operating the swirling means for production of swirling in order to spin a thread from the individual fibers, fed via the opening channel segment (6). into the spinning segment (13).
 15. The method according to claim 14, wherein the fluid comprises compressed air. 